E May 1942:
During her trials, a maximum speed of 26 knots is reached.

8 May 1942:
JUNYO arrives at Saeki Wan (Bay), northeast Kyushu.
18 May 1942:
JUNYO's air group flies onboard from Saeki air base.
19 May 1942:
Departs Saeki Wan (Bay) for Kure. That same day, near Kure, almost sideswipes the new super-battleship YAMATO, undergoing battle-training.
20 May 1942:
Assigned to the Second Carrier Striking Force, Northern Force for the upcoming “MI/AL” Operation.
22 May 1942:
Departs Kure for Ominato with RYUJO, screened by destroyers AKEBONO, AKATSUKI, HIBIKI, IKAZUCHI, and INAZUMA.
25 May 1942:
Arrives at Mutsu Wan (Bay), Ominato. JUNYO’s aircraft complement is still incomplete, only consisting of 18 Mitsubishi Type 0 A6M2 “Zeke” (including 12 aircraft from the 6th Air Group) and 15 Aichi D3A1 “Val”. No attack aircraft (B5N) unit is embarked.
26 May 1942: Operation "AL" - The Seizure of Attu and Kiska:
Vice Admiral Hosogaya Boshiro's (36) (former CO of MUTSU) Northern Force's Main Body's CruDiv 5's NACHI (F) and destroyers INAZUMA and IKAZUCHI accompanying Rear Admiral (Vice Admiral posthumously) Kakuta Kakuji, (39) (former CO of NAGATO) Second Carrier Striking Force's CarDiv 4's JUNYO (F) and RYUJO, CruDiv 4's TAKAO and MAYA, Desdiv 3 SHIOKAZE and DesDiv 7 AKEBONO, USHIO, and SAZANAMI, auxiliary transport AKASHISAN MARU, auxiliary storeship TOKO MARU No. 2 GO, oiler FUJISAN MARU, collier/oiler NISSAN MARU and auxiliary cruiser AWATA MARU depart Mutsu Wan (Bay), Ominato for the Aleutians.
29 May 1942:
Rear Admiral (later Vice Admiral) Omori Sentaro's (41) (former CO of ISE) Adak-Attu Invasion Force: DesRon 1's light cruiser ABUKUMA, DesDiv 21's HATSUHARU, HATSUSHIMO, WAKABA and NENOHI, auxiliary transport KINUGASA MARU, fleet supply ship MUROTO and auxiliary minelayer MAGANE MARU departs Mutsu Wan (Bay).
Admiral Omori’s Adak-Attu Invasion Force accompanies Captain (later Rear Admiral) Ono Takeji's (44) Kiska Invasion Force: CruDiv 21’s TAMA and KISO, DesDiv 6’s HIBIKI and AKATSUKI, Fifth Fleet’s destroyer HOKAZE, auxiliary cruiser ASAKA MARU and auxiliary transports HAKUSAN and KUMAGAWA MARUs.
1 June 1942:
The Invasion Force arrives at Paramushiro, Kuriles. Departs the same day for the Aleutians.
3 June 1942:
The Second Carrier Striking Force is detached and launches air attacks against American installations in the Aleutians at Dutch Harbor and Unalaska Island. At 0325, first strike is launched with 46 aircraft to which JUNYO contributes 15 D3A1s escorted by 13 A6M2s. However, the pilots most flying their first combat flight don’t deal well with the weather conditions and abort mission. Only two A6M2s continue to Dutch Harbor. The other aircraft, on their way back to the carrier spot a Consolidated PBY “Catalina”, on recon patrol. The seaplane is quickly shot down by the A6M2s and ditches while on fire. Three survivors are later rescued by TAKAO and taken to Japan as POWs. No aircraft losses are sustained.
At 1045, Kakuta decides to launch a second strike aiming the destroyers previously spotted by RYUJO’s aircraft at Makushin Bay, with 47 aircraft to which JUNYO contributes 15D3A1s escorted by 6 A6M2s. This time, foul weather and icing in carburetors force all aircraft to abort mission and return safely to their carrier.
4 June 1942:
At 1640, a third strike totaling 31 aircraft is launched, this time against Dutch Harbor, to which JUNYO contributes 10 D3A1s escorted by 5 A6M2s. By 1810, they bomb oil tanks, AA positions, part of a hospital and the naval air station and peer. On their way back, they are intercepted by 9 Curtiss P-40s “Warhawk”. In the ensuing air battle, the A6M2s claim 5 P-40s for the loss of 4 D3A1s and 5 D3A1s damaged. At 2026, plane recovery completed, after having earlier received orders to join forces with Vice Admiral (Admiral posthumously) Nagumo Chuichi’s (36) forces, the Second Carrier Strike Force dutifully heads south at high speed.
5 June 1942:
Combined Fleet’s previous order is cancelled. Kakuta’s force remains in northern waters. About 0900, it is attacked by U.S. land-based Martin B-26 “Marauder” equipped with torpedoes, but no damage is sustained.
6 June 1942:
The Second Carrier Striking Force rejoins the Northern Force to cover the invasion of Attu and Kiska Islands.
BatDiv 3/1's HIEI and KONGO, CarDiv 3's ZUIHO and seaplane carrier KAMIKAWA MARU detach from Vice Admiral (later Admiral) Kondo Nobutake's (35) (former CO of KONGO) Midway Invasion Force with Rear Admiral (later Vice Admiral) Abe Hiroaki's (39) (former CO of FUSO) CruDiv 8's TONE and CHIKUMA and join the Second Carrier Striking Force SW of the Aleutians.
7 June 1942:
Vice Admiral Hosogaya's Fifth Fleet captures Attu and Kiska.
E June 1942:
As a result of the lessons learned from “MI” Operation, the ship’s fighter complement is increased to 21 A6Ms and the other aircraft reduced to 12 D3As and 9 B5Ns.
24 June 1942:
Arrives at Ominato.
28 June 1942:
Departs Ominato for the Aleutians in Rear Admiral Kakuta's Second Mobile Force: CarDiv 4's also consisting of RYUJO and ZUIKAKU, CarDiv 3’s ZUIHO escorted by CruDiv 5's HAGURO, MYOKO and NACHI, CruDiv 21's KISO and TAMA, DesRon 1’s light cruiser ABUKUMA, DesDiv 4's ARASHI, MAIKAZE, HAGIKAZE and NOWAKI, DesDiv 7's USHIO, SAZANAMI, DesDiv 9's ASAGUMO, MINEGUMO and NATSUGUMO, DesDiv 10's AKIGUMO, KAZAGUMO, MAKIGUMO and YUGUMO, DesDiv 17's URAKAZE and the Fifth Fleet’s destroyer SHIOKAZE.
The mission is to cover the second reinforcement convoy to Kiska, then patrols SW of Kiska in anticipation of an American counter-attack.
7 July 1942:
Departs Aleutians waters.
13 July-End July 1942:
Arrives at Kure for maintenance and refit. The carrier finally gets the two missing Type 94 high-angle fire-control directors and is fitted with one Type 21 air search radar placed on the top of the island. Following the loss of four fleet carriers at Midway, JUNYO is re-designated as a regular carrier.
14 July 1942:
As part of the great post-Midway fleet reorganization, reassigned with light carrier RYUJO to Mobile Force, Air Attack Force in Rear Admiral Kakuta’s CarDiv 2, 3rd Fleet.
20 July 1942:
Captain Ishii is relieved by Captain (later Rear Admiral) Okada Tametsugu (45) (former CO of heavy cruiser TONE) as commanding officer.
28 July 1942:
Departs Kure.
31 July 1942:
Arrives at Iwaishima. On the same day, her sister-ship HIYO joins Cardiv 2.
E August-September 1942:
Inland Sea. Undergoes intensive training exercises to her air group with sister-ship HIYO, DesDiv 16’s YUKIKAZE (August only), DesDiv 19’s ISONAMI and DesDiv 6’s IZANUMA (September only).
13 August 1942:
Enters drydock at Kure for minor repairs.
22 August 1942:
Undocked.
14 September 1942:
Off Saeki. JUNYO’s air group is part of a major training exercise.
4 October 1942:
Rear Admiral Kakuta's CarDiv 2 departs Saeki for Truk, Central Carolines escorted by DesDiv 19's ISONAMI and DesDiv 6's IZANUMA. JUNYO's aircraft complement consists of 21 A6M2s, 18 D3A1s and 9 B5N2s.
9 October 1942:
Arrives at Truk. Assigned to Main Unit Advance Force (CarDiv 2, Third Fleet).
11 October 1942:
Departs Truk in the preliminaries to the Battle of Santa Cruz in Rear Admiral (later Vice Admiral) Kakuta Kakuji's (39) (former CO of YAMASHIRO) Advance Force's CarDiv 2's also consisting of sister-ship HIYO and DesDiv 15's HAYASHIO and KUROSHIO.
CarDiv 2 is accompanied by Rear Admiral (later Vice Admiral) Abe Hirohaki's (39) Vanguard Force: BatDiv 11's HIEI and KIRISHIMA, CruDiv 7's SUZUYA, CruDiv 8's TONE and CHIKUMA, DesRon 10's NAGARA, DesDiv 10's MAKIGUMO, KAZAGUMO, AKIGUMO and YUGUMO and DesDiv 17's URAKAZE, TANIKAZE and ISOKAZE.
Abe and Kakuta's forces are followed by Nagumo's Carrier Strike Force's CarDiv 1's SHOKAKU, ZUIKAKU and ZUIHO, CruDiv 7's KUMANO, DesDiv 16's AMATSUKAZE, HATSUKAZE, TOKITSUKAZE and YUKIKAZE, DesDiv 4's ARASHI, MAIKAZE and DesDiv 61's TERUZUKI.
14 October 1942:
Cardiv 2 from a holding position 200 miles north of Guadalcanal launches planes throughout the day to furnish CAP and anti-submarine patrol cover for battleships KONGO and HARUNA of Batdiv 3 returning from successful bombardment of Henderson field early that morning. That afternoon, cover is also provided for Tanaka's advancing transport force.
16-17 October 1942:
Rear Admiral Kakuta’s CarDiv 2 is ordered to launch an airstrike on the US transports moored off Lunga Point, Guadalcanal. In the night of 16 ‘Oct, JUNYO and HIYO head south to their launching spot, 180 miles N of Henderson Field.
At 0515, 18 B5N2s (9 from each carrier), with a 800kg bomb, escorted by 18 A6M2s (9 from each carrier) take off and head to the target. However one B5N2 from JUNYO aborts mission due to mechanical trouble and returns to its carrier.
At 0700, Florida Island is sighted and both Air Groups commanders decide to attack USS AARON WARD (DD-483) and LARDNER (DD-487), both ships on a shore bombardment mission targeting Japanese supply dumps.
At 0727, HIYO’s 9 B5N2s target AARON WARD but score no hits, losing one B5N2 from AA fire. Shortly afterwards, JUNYO’s 9 B5N2s target LARDNER but are engaged by VMF-121 F4F “Wildcats”. In the ensuing battle, 3 B5N2s are shot down and 2 damaged.
At 0735, without scoring any hit on LARDNER, 3 additional B5N2s are shot down by the F4Fs and AA fire, for the loss of only one F4F, shot down by the escorting A6M2s. Finally, one damaged B5N2 ditches near Rekata Island and two others land at Buin. Of the nine JUNYO’s B5N2s, only one returns safely (the one that aborted mission). The first operation of CarDiv 2 is a total failure.
21 October 1942:
A fire breaks out in HIYO’s generator room at 1930 and heavily damages the condenser. The carrier’s speed is reduced to 16 knots.
22 October 1942:
Admiral Kakuta’s flag is transferred to JUNYO as well as 3 A6M2s, 1 D3A1 and 5 B5N2s from HIYO. The latter returns to Truk for emergency repairs, escorted by DesDiv 19’s ISONAMI and DesDiv 6’s IZANUMA.
25 October 1942:
Launches six bombers and twelve fighters which attack Henderson Field at 1350, suffering no losses, but inflicting little damage.
26 October 1942:
Assigned to Striking Force, bombed in South Pacific engagement, but no damage.
At 0705, JUNYO, the only carrier not spotted by US forces, launches a first strike consisting of 17 D3A1s escorted by 12 A6M2s.
At 0818, Nagumo orders JUNYO to close ZUIKAKU and coordinate with her.
At 0845, JUNYO is detached and heads to CarDiv 1’s position escorted by DesDiv 15’s HAYASHIO.
0921-0926: JUNYO’s first airstrike’s carrier-bombers attack TF-16. 10 D3A1s target ENTERPRISE. No hits are scored and 8 aircraft are shot down. A bomb hits SOUTH DAKOTA’s “A” main turret but fails to penetrate armor. 50 sailors, including her CO, Captain (later Rear Admiral-Ret)Thomas L. Gatch (USNA ’12), are wounded by the explosion’s blast. 2 D3A1s attack USS SAN JUAN (CL-54). One bomb hits the cruiser, temporarily disabling her rudder.
At 1106 launches a strike (second of the day) of 7 B5N2s escorted by 8 A6M2s.
At 1310 these attack the crippled U.S. carrier HORNET, frustrating a tow attempt by heavy cruiser NORTHAMPTON. This strike scores a devastating torpedo hit in the starboard after engine room of the carrier at 1323, knocking out all remaining power and thwarting further salvage attempts. (HORNET is subsequently sunk by destroyers of the Advance Force after failed scuttling attempts by USN destroyers). Two B5N2s and two A6M2s are lost.
At 2100, three radar-equipped Consolidated PBYs armed with bombs and torpedoes attack ZUIKAKU and JUNYO. A near-miss off the starboard beam damages DesDiv 61’s TERUZUKI, but the carriers are not hit.
27 October 1942:
At 1332, Flag of CarDiv 1 is transferred to ZUIKAKU from DesDiv 4’s ARASHI as Nagumo finally catches up with the carrier. Recalled, the battle over, ZUIKAKU and JUNYO head for Truk.
29 October 1942:
At 0645, a JUNYO plane sights and bombs an enemy submarine. (Identity unknown).
30 October 1942:
Both carriers arrive at Truk.
9 November 1942:
At 1100, departs Truk for Ontong Java area with BatDiv 3’s KONGO and HARUNA CruDiv 4’s ATAGO and TAKAO, CruDiv 8’s TONE, DesRon 3's light cruiser SENDAI, DesDiv 11's HATSUYUKI and SHIRAYUKI and DesDiv 19's AYANAMI, SHIKINAMI and URANAMI to cover a major convoy to reinforce Guadalcanal. JUNYO’s aircraft complement consists of 27 A6Ms, 12 D3A1s and 9 B5N2s. The new air group is a composite one from various units available at Truk. Two D3A1s scouts are launched but fail to find USS ENTERPRISE (CV-6) south at Guadalcanal.
10 November 1942:
During the day, launches search patrols consisting of 2 D3A1s and 2 B5N2s.
11 November 1942:
Launches search patrols consisting of 3 D3A1s.
12 November 1942:
Launches fighters to provide close cover to the ships enroute to Guadalcanal.
Night 12-13 November 1942:
At 0330, launches 8 A6M2s guided by 2 B5N2s scouts to provide close cover to the disabled HIEI. Intercepted by 7 F4F “Wildcat” from Guadalcanal, 3 covering A6M2s "Zeke" are shot down.
At 0430, launches 6 A6M2s guided by one B5N2 scout to again provide cover to HIEI. Other patrols are to follow the next morning.
13 November 1942:
At 0515, HIEI is attacked by four Grumman TBF-1 "Avenger" torpedo bombers from Henderson Field, Guadalcanal. 3 A6M "Zeros" from JUNYO attempt to intercept the attackers, damaging one heavily.
At 0737, KIRISHIMA is ordered to close JUNYO force off Ontong Java, and abandon her attempt to go to the rescue of crippled battleship HIEI. Instead, JUNYO launches 9 A6M2s guided by 3 D3A1 scouts in a last attempt to help defend crippled battleship HIEI; they arrive late, at 1135, because they had been given the wrong position. They attempt to stop the final aerial torpedo attacks from planes of USS ENTERPRISE at 1230, but to no avail, and the salvage effort on HIEI is fatally compromised by two additional torpedo hits. The battleship has to be abandoned and left to sink. Additionally, two A6M2s are lost.
14 November 1942:
DesRon 3's SENDAI with DesDiv 19 forms a Sweeping Unit. CarDiv 2's JUNYO, battleships KONGO and HARUNA and the remainder of Kondo's Second Fleet Advanced Force are to hold station as distant cover E of Ontong Java. During the day, launches search patrols totaling 2 B5N2s, 9 A6Ms and 5 (2+3) D3A1s. One search patrol consisting of 9 A6Ms and 3 D3A1s heads to Tulagi and, at 1040, spots USS PORTLAND (CA-33) and USS AARON WARD (DD-483), both crippled in the previous night battle.
15 November 1942:
Search patrols are launched for a total of 4 (2+2) B5N2s.
16 November 1942:
Search patrols are launched for a total of 5 (4+1) B5N2s . Destroyers SAMIDARE and HARUSAME, with KIRISHIMA and YUDACHI survivors aboard respectively, refuel while JUNYO provides them air cover.
18 November 1942:
Search patrols with 3 B5N2s. At 0830, arrives at Truk.
4 December 1942:
Reassigned to Third Fleet, CarDiv 2.
16 December 1942: Operation "MU"-The Reinforcement of Wewak.
Departs Truk with DesRon 10’s light cruiser AGANO and DesDiv 17’s ISOKAZE and HAMAKAZE to cover a troop convoy led by light cruiser TENRYU to Wewak and Madang, New Guinea.
17 December 1942:
Just before noon, the JUNYO group is spotted by LtCdr Lucius H. Chappell’s (USNA ’27) USS SCULPIN (SS-191) moving southwestward, but SCULPIN can get no closer to the carrier than nine miles.
18 December 1942:
Shortly before midnight, the JUNYO group spots SCULPIN running on the surface. At 5,000 yards, DesDiv 17 opens fire at the submarine, but SCULPIN submerges and escapes.
JUNYO group operates in the Bismarck Sea and covers the occupation of Hollandia (now Jayapura).
20 December 1942:
JUNYO group arrives back at Truk.
E December 1942:
Decision is made to alter again her air group by replacing six D3As by an equal number of A6Ms.
12 January 1943:
Assigned to Southeast Area Force, Outer South Seas Support Force. At Truk throughout except period 16th through 18th.
16 January 1943:
Departs Truk with Desdiv 9’s ASAGUMO and SAMIDARE to cover "HEI No. 1" convoy bound from Palau to Wewak consisting of auxiliary transports (ex-seaplane tenders) SANUKI and SAGARA MARUs escorted by Rear Admiral (later Vice Admiral) Kishi Fukuji's (40) Combined Fleet’s light cruisers KITAKAMI and OI. The convoy transports the IJA’s 20th Infantry division consisting of 9,443 men, 82 vehicles, weapons and 12,267 bundles of provisions.
17 January 1943:
At 1030, JUNYO launches 21 fighters and 6 attack-planes to fly to the airfield at Wewak. She then reverses course.
19 January 1943:
At 1530, the convoy arrives at Wewak, New Guinea and begins landing operations. JUNYO and her escort return to Truk after a submarine scare south of the atoll. Some of her A6M2s ‘Zeke” fighters are detached to Wewak to provide close protection to the landings.
25 January 1943:
Resumes assignment with Forward Force Air Force, Third Fleet, CarDiv 2. JUNYO's planes arrive back at Truk having flown from Wewak on the 23rd with stopover at Kavieng.
31 January 1943: Operation "KE" - The Evacuation of Guadalcanal:
Second and Third Fleets including carriers JUNYO, ZUIKAKU, ZUIHO, BatDiv 3's KONGO and HARUNA, DesRon 10’s light cruiser AGANO and destroyers ISOKAZE and HAMAKAZE, CruDiv 4's ATAGO and TAKAO, CruDiv 5's HAGURO and MYOKO and DesRon 4's light cruiser NAGARA and destroyers steam from Truk to an area N of the Solomons as a feint to cover Rear Admiral (later Vice Admiral) Hashimoto Shintaro's (41) (former CO of HYUGA) destroyer force from Rabaul.
9 February 1943:
Arrives at Truk. By this date, the Japanese successfully evacuate 11,700 troops from Guadalcanal.
12 February 1943:
Captain Okada is relieved by Captain (later Rear Admiral) Nagai Mitsuru (45) (former CO of target ship [ex battleship] SETTSU) as commanding officer.
16 February 1943:
Departs Truk for Inland Sea with DesDiv 15’s KAGERO and KUROSHIO and NOWAKI. Embarked are some 50 damaged aircraft which will be repaired in Japan.
22 February 1943:
Arrives at Kure for maintenance and refit.
E February-March 1943:
Two Type 95 directors for the 25mm AA guns are added. The carrier is also fitted with a second Type 21 air search radar placed on the port side of the hull, outboard of the rear elevator.
16 March 1943:
Departs Kure for Saeki.
22 March 1943:
With sister-ship HIYO, departs Saeki for Truk with Crudiv 8 TONE and CHIKUMA and DesDiv 61’s SUZUTSUKI and HATSUZUKI, DesDiv 15’s KAGERO and DesDiv 27’s YUGURE.
27 March 1943:
Arrives at Truk.
1 April 1943: Operation "I-GO" - The Reinforcement of Rabaul:
Assigned to contribute aircraft to "I" Operation activated by Commander-in-Chief Yamamoto Isoroku this day. Aircraft from CarDiv 1's ZUIKAKU and ZUIHO are detached to reinforce the 11th Air Fleet's base at Rabaul and aircraft from CarDiv 2's HIYO and JUNYO to reinforce the base at Ballale Island, near Buin.Vessel itself remains at Truk.
7 April 1943:
Cardiv 2's planes achieve notable results. Off Tulagi, Junyo’s aircraft hit destroyer USS AARON WARD (DD-483) with five bombs, while Hiyo's planes strike fleet tanker USS KANAWHA (AO-1) and New Zealand navy's gunboat HMNZS MOA (T-233). The latter sinks within minutes, USS AARON WARD goes down stern first at 1835 (2135 local). USS KANAWHA had preceded her.
14 May 1943:
Cardiv 2's aircraft attack Milne Bay, New Guinea. They hit and sink Dutch freighter VAN HEEMSKERK carrying troops and equipment. Four crewmen are KIA.
3 May 1943:
Assignment changed to Forward Force Air Force, under tactical command of forward force. Vessel remains at Truk through end of month.
15 June 1943:
Assignment changed to Eastern Force Carrier force, still under tactical command of forward force. Continues to remain at Truk throughout.
21 June 1943:
1600: Becomes flagship of Cardiv 2 after flag is shifted from RYUHO arriving this day from Yokosuka.
2 July 1943:
JUNYO’s air group is deployed at Buin, Bougainville in response to the 30 June American landings at Rendova Island, Solomons.
8 July 1943:
Departs Truk on a ferry-aircraft mission escorted by light cruiser NAGARA.
10 July 1943:
Assigned to Striking Force (3rd Fleet, CarDiv 2) also consisting of light carrier RYUHO.
11 July 1943:
Arrives at Roi Island, Kwajalein. Delivers the aircraft she is ferrying. Departs later in the day, still escorted by NAGARA.
13 July 1943:
Arrives at Truk. Embarks more aircraft.
14 July 1943:
Departs Truk, still escorted by NAGARA.
15 July 1943:
Arrives at Kavieng and delivers the aircraft she is ferrying. While mooring, NAGARA detonates a mine laid at night by RAAF PBYs "Catalina" flying boats. The mine slightly damages her bottom under the stern, but she is able to operate.
16 July 1943:
Departs Kavieng.
17 July 1943:
Arrives at Rabaul and delivers the aircraft she is ferrying. Departs the same day for Truk with NAGARA and DesDiv 27’s ARIAKE and SHIGURE.
19 July 1943:
Arrives at Truk. Departs later that same day for Kure with light carrier RYUHO, escort carriers UNYO and CHUYO and destroyers TANIKAZE, USHIO, AKEBONO, and UMIKAZE. JUNYO and RYUHO’s air groups remain at Buin.
22 July 1943:
Early this afternoon some of Cardiv 2's aircraft try to cover and defend seaplane-carrier NISSHIN when attacked off Bougainville. Nonetheless, the ship is sunk.
24 July 1943:
UNYO and CHUYO separate with Desdiv 7’s AKEBONO and USHIO and head for Yokosuka.
25 July 1943:
Arrives at Kure with RYUHO, reassigned to Combined Fleet.
26 July 1943:
Enters drydock at Kure for maintenance and refit.
31 July 1943:
Undocked. Four Type 96 triple 25mm AA mounts are added.
9 August 1943:
Departs Kure and arrives at Iwakuni later that day.
15 August 1943:
Departs Saeki for Singapore on plane-ferrying duty with DesDiv 17’s TANIKAZE. JUNYO is transporting the 331st Air Group consisting of 36 A6Ms “Zeke” fighters and 18 B6N2 “Jill” attack planes bound to Sabang Airbase, Sumatra.
27 August 1943:
Off Singapore. All 331st Air Group’s aircraft take off and fly to Sabang.
28 August 1943:
Arrives at Singapore.
1 September 1943:
Cardiv 2's aircraft fly into Singapore, having been pulled back after heavy losses for reconstitution.
4 September 1943:
Departs Singapore for Inland Sea, still escorted by DesDiv 17’s TANIKAZE.
11 September 1943:
Arrives at Kure, subsequently shifts to Iwakuni.
19 September 1943:
Departs Iwakuni for Truk as part of “TEI No. 1”, third echelon, troop transport mission with about 1,000 army troops and equipment, some belonging to the 107th Infantry Regiment, 52nd Division, bound for the Carolines, still with DesDiv 17’s TANIKAZE.
24 September 1943:
Arrives at Truk and disembarks troops and equipment.
28 September 1943:
Assignment changed from Combined Fleet to Striking Force, 3rd Fleet, CarDiv 2.
29 September 1943:
Departs Truk for Kure with KISO escorted by DesDiv 32’s TAMANAMI.
5 October 1943:
Arrives at Kure.
12 October 1943:
Departs Iwakuni for Truk in "TEI No. 3" troop transport mission also consisting of CruDiv 18's light cruiser TATSUTA, DesDiv 32's FUJINAMI, SUZUNAMI, TAMANAMI and HAYANAMI. About 2,000 men are lifted between the various ships.
15 October 1943:
"TEI No. 3" troop transport mission rendezvous at sea with BatDiv 2’s YAMASHIRO and ISE.
19 October 1943:
Arrives at Truk and debarks troops.
31 October 1943:
At 0800, departs Truk for Kure with BatDiv 2’s ISE and YAMASHIRO, CruDiv 8's TONE, CruDiv 18's TATSUTA, DesDiv 17's TANIKAZE and DesDiv 24's UMIKAZE and SUZUKAZE. The Force later rejoins escort carrier UNYO and DesDiv 7's AKEBONO that departed the previous day.
1 November 1943:
Singapore. JUNYO’s air group has been reconstituted and consists now of 24 A6Ms, 18 D3As and 9 B5Ns.
4 November 1943:
Escort carrier UNYO and DesDiv 7's AKEBONO separate and head for Yokosuka.
5 November 1943:
At 0400, the zigzagging task group is picked up on radar in the Bungo Suido by LtCdr (later Admiral) Ignatius. J. "Pete" Galantin's (USNA ’33) USS HALIBUT (SS-232). Identified as 1 ACV, 2 BB, 1 CA and several DDs course 300, 19 knots.
At 0539, Galantin fires six bow torpedoes at JUNYO. At 0540, the first torpedo of the spread hits JUNYO in the starboard quarter. Four men are killed and steering gear is destroyed. The rudder is jammed five degrees right, and there is some damage to the propeller shafts. Stern settles, but flooding and list are minimal. The other five torpedoes miss astern. It appears one of the misses of the first salvo hits YAMASHIRO, which was then on JUNYO's port quarter, but it fails to explode.
At 0543, Galantin fires two stern torpedoes at the carrier but they miss. At 0558, Galantin tries to fire another torpedo at JUNYO but it malfunctions and "runs hot" in the tube. The screen drives away the submarine and emergency repairs continue. At 1541, the carrier signals that despite some vibrations in the shafts she can make turns for 15 knots. However, because of the damaged rudder, she cannot proceed on her own power and TONE has to take her in tow to bring her into Kure.
19 November 1943:
Enters drydock for repairs of torpedo damage.
1 December 1943:
JUNYO’s air group is transferred to Truk.
25 November 1943:
Undocked. Remains at Kure through the end of 1943.
21 December 1943:
Enters drydock for maintenance and refit. Remains there till the end of Feb ‘44.
25 December 1943:
Captain Nagai is relieved by Captain (later Rear Admiral) Shibuya Kiyomi (45) (former CO of light cruiser KUMA) as commanding officer.
E end of December 1943:
JUNYO’s air group is transferred to Kavieng, New Ireland.
25 January 1944:
JUNYO’s air group is transferred to Vunakanau Airfield, Rabaul.
19-21 February 1944:
After losing more than half of his fighting power, the remnants of CarDiv 2’s air group, consisting of 15 A6Ms, 14 D3As and 8 B5Ns, are transferred to Truk. JUNYO’s air group is subsequently disbanded.
29 February 1944:
Undocked. Four Type 96 triple 25mm AA mounts are added, two are mounted on the stern and the others are placed in front of and behind the island. 12 Type 96 single 25mm AA mounts are also added, some of which are portable and can be mounted on tie-down points on the flight deck.
2 March 1944:
JUNYO’s aircrew depart Truk for mainland without their aircraft.
10 March 1944:
Creation of the 652nd Air Group assigned to CarDiv 2. At full strength, the Air Group should consist of 81 fighters, 36 dive-bombers and 27 attack planes, totaling 144 aircraft.
26 March 1944:
Departs Kure for Iwakuni.
1 April 1944:
The 652nd Air Group still is not at full strength and only consists of 30 A6M2 and 13 A6M5 fighters and 4 D3A2 dive-bombers.
April 1944:
In Iwakuni-Kure area throughout month. Engages in intensive training with the 652nd Air Group.
3 May 1944:
At Kure, conduct a series of inclination and damage control trials.
6 May 1944:
Off Iwakuni, JUNYO's new 652nd Air Group members fly out from their bases and land aboard her. After recovering them, she proceeds to Saeki.
11 May 1944:
Departs Saeki, Japan for Tawi Tawi, Philippines via Okinawa with CarDiv 2's JUNYO and RYUHO and CarDiv 3's ZUIHO, CHIYODA, CHITOSE super-battleship MUSASHI and DesRon 11's AKISHIMO and HAYASHIMO, DesDiv 4's MICHISHIO, NOWAKI and YAMAGUMO, DesDiv 27's SHIGURE and DesDiv 32's TAMANAMI. CarDiv 2 carries a still incomplete Air Group No. 652 consisting of 135 aircraft: 27 A6M2 fighters – to be used in a fighter-bomber role, armed with a 250kg bomb – 53 A6M5 fighters and 55 dive-bombers and attack planes.
12 May 1944:
Arrives at Nakagusuku Wan (Bay), Okinawa. Departs later in the day for the Mobile Fleet operating base at Tawi Tawi.
16 May 1944:
Arrives at Tawi Tawi and joins Mobile Fleet of Admiral Ozawa.
E May-June 1944:
Tawi-Tawi. Engages in training but only a few times due to the presence of US submarines and the lack of an airfield in the area.
13 June 1944: Operation "A-GO" - The Battle of the Philippine Sea:
In Tokyo, the CINC, Combined Fleet, Admiral Toyoda Soemu, (33) (former CO of HYUGA), sends out a signal that activates the A-GO plan for the Defense of the Marianas.
At 0900, Ozawa's Mobile Fleet departs Tawi Tawi (less Operation "Kon's" BatDiv 1, CruDiv 5 and screen) for Guimaras near Panay Island, Philippines. JUNYO is in Rear Admiral Joshima Takatsugu's (40) Force "B" also consisting of CarDiv 2's HIYO and RYUHO, BatDiv 1's NAGATO, CruDiv 7's MOGAMI, DesRon 2's HAYASHIMO, DesDiv 4's MICHISHIO.
At 0900 (H-time, 1000 JST), LtCdr (later Cdr) Marshall H. Austin's (USNA '35) USS REDFIN (SS-272) on station outside the anchorage, sights and at 2100 (JST) reports the fleet departing.
14 June 1944:
Guimaras. Refuels from the 2nd Supply Force oilers GENYO and AZUSA MARUs.
15 June 1944:
At 0800, the Mobile Fleet departs Guimaras through the Visayan Sea. At 1622 (H-time/1722 JST), LtCdr (later Captain) Robert Risser's (USNA '34) USS FLYING FISH (SS-229) sights the Mobile Fleet exiting the San Bernardino Strait. At sunset, he surfaces and at 2025 (JST) reports the contact.
Ozawa's forces refuel from the 1st Supply Force oilers HAYUSUI and NICHIEI, KOKUYO and SEIYO MARUs.
Forces “A” and “B” deploy 100 miles behind Vice Admiral Kurita Takeo's (38) former CO of KONGO) Vanguard Force "C.”
17 June 1944:
In the morning CarDiv 2's screen is reinforced by destroyers NOWAKI and YAMAGUMO.
At 1800 CarDiv 2' s screen is reinforced by destroyers SHIGURE, SAMIDARE, AKISHIMO and HAMAKAZE detached from 1st Replenishment tanker group.
At 2000 JST, LtCdr (later Rear Admiral) Herman J. Kossler's (USNA '34) USS CAVALLA (SS-244) sights the Mobile Fleet in the Philippine Sea and at 2245 reports its movement after surfacing later that evening.
18 June 1944:
At 2100, Ozawa splits the Mobile Fleet. Forces “A” and “B” proceed southward. The Vanguard Force “C” proceeds due east.
19 June 1944:
CarDiv 2's 652nd Air Group consists of 53 A6M5 fighters, 27 A6M2 fighter-bombers, 15 Nakajima 'Tenzan' B6N2 “Jill” attack planes, 11 Yokosuka Type 2 'Suisei' D4Y1 “Comet” and 29 D3A2 dive-bombers. CarDiv 2 doesn't take part in the first two airstrikes (So-called Raid I and Raid II.)
At 0950, CarDiv 2's first airstrike (the third of the day) is launched, consisting of 25 A6M2 fighter-bombers, 7 B6N2 torpedo-equipped escorted by 15 A6M5 fighters. During their outbound leg, they are redirected towards a new position but only about 20 aircraft receive the radio-message and duly change their course, the other aircraft, after failing to spot Task Force 58, return to their respective carriers. The airstrike, hence reduced to a mere 20 aircraft, fails to score any hit for the loss of 7 A6Ms.
Ozawa orders a fourth strike to be launched totaling 70 aircraft to which JUNYO contributes 9 D3A2s escorted by 6 A6M5s, the first aircraft taking off at 1015. However, that airstrike is, once again, a complete failure as the planes are instructed to fly to position “15 Ri”, a wrong spot where TF 58 is absent. After circling for 30 minutes in vain, JUNYO's aircraft head to Guam and arrive there at the same time as a USN aircraft raid. In the ensuing air battle, 3 A6M5 and 7 D3A2 are shot down by the F6Fs “Hellcat” for the loss of 6 “Hellcats”.
Meantime, at 1030, JUNYO launches a second wave consisting of 9 D4Y1s escorted by 6 A6M5s. Shortly after taking off, 2 D4Y1 abort mission, due to a faulty landing gear and head to Yap, and one A6M5 experiencing mechanical trouble returns to the carrier. At 1340, the remaining aircraft attack Task Force 58, targeting USS WASP (CV-18) but score no hits. 4 A6M5s and 5 D4Y1s are shot down, the surviving aircraft landing at Guam and at Rota.
To summarize, the Mobile Fleet has launched that day 374 aircraft, including floatplanes, in four raids against Admiral Raymond A. Spruance's (USNA '06) Task Force 58. In the "Great Marianas Turkey Shoot", Ozawa has lost 244 planes in the raids. Spruance has lost 22 aircraft in the fighting including some to flak on Guam. The 652th Air Group is reduced to 46 aircraft – 19 A6M5, 19 A6M2 and 8 B6N2 – to be compared to an initial strength totaling 135 aircraft.
20 June 1944:
On the second day of Battle of the Marianas, TF-58 aircraft attack Ozawa’s Mobile Fleet. JUNYO is attacked around 1750. She is hit on the island against the stack by one or two 250 kg bombs. The smokestack is utterly crushed and goes overboard and the mast shattered. Flying fragments and blast kill many lookouts and signal men, but fortunately do little harm to the bridge. Fires are started in the island superstructure. At the same time numerous near-misses buckles the flight deck and perforates the fantail causing minor flooding in the steering room. Though air operations are stopped, damage is moderate. However, JUNYO lost 53 men killed, almost all of them lookouts and signal men. Three A6Ms are lost for one SBD “Dauntless” shot down by JUNYO’s combat air patrol (CAP). Attempts to standby torpedoed sister-carrier HIYO, but withdraws soon after. At the day’s end, the 652nd Air Group is reduced to about 20~25 aircraft – 11 A6M5s, 5 A6M2, 1 B6N2 and the few aircraft that have landed at Yap, Rota and Guam. Admiral Toyoda orders the Mobile Fleet to retire to Nakagusuku Wan (Bay), Okinawa.
22 June 1944:
Arrives at Nakagusuku Wan (Bay), Okinawa for refueling, then departs.
24 June 1944:
The Mobile Fleet arrives at Hashirajima.
3 July 1944:
Departs Hashirajima for Kure, stays there for remainder of July.
6 July 1944:
Enters drydock for repair battle-damage and refit.
10 July 1944:
Assignment changes from Striking Force, Third Fleet, CarDiv 2, to Striking Force, Third Fleet, CarDiv 4 also consisting of battleships/carriers ISE and HYUGA. Both CarDiv 2 and 652th Air Group are disbanded.
14 July 1944:
Undocked. Three Type 96 triple 25mm AA mounts are added to reinforce her AA armament as well as two Type 96 twin 25mm AA mounts and 18 Type 96 single 25mm AA mounts. At this time assigned complement is 1,330 officers and men.
10 August 1944:
Light carrier RYUHO is assigned to CarDiv 4 with ISE, HYUGA and JUNYO. Air Group No. 634, assigned to CarDiv4, totals 130 aircraft.
21 August 1944:
Departs Kure; thereafter in Hashirajima area and vicinity.
11 September 1944:
Departs Hashirajima and arrives at Kure later that day for a refit.
26 September 1944:
Her AA armament is bolstered by six racks of 30-tube (180) 127mm. (5-inch) AA phosphorous rocket launchers mounted in sponsons on each beam far aft. The rockets are armed with multiple incendiary shrapnel charges and a time fuze. The launching crews must wear special protective suits and withdraw prior to each launch. The carrier’s light AA armament consists now of a total of 91 25mm tubes: 57 in 19 triple mounts, four in two twin mounts and 30 single mounts. The carrier is also fitted with one Type 13 air search radar placed on the mast aft of the island.(Note 1)
Departs Kure and arrives at Iwakuni later in the day. There she commences training with her new air group, the 634th Air Group.
11 October 1944:
Off Tokuyama. By this time JUNYO's 634th Air Group had been detached from her and ordered to fly down to Formosa, where they suffer heavy losses during U.S. TF 38's Formosa raids in that period.
21 October 1944:
Shifts to Kure.
27 October 1944:
Assigned to special transport mission for Philippine Operations.
28 October 1944:
Arrives at Sasebo.
30 October 1944:
On special transport mission for 1st Diversion Attack Force; with light cruiser KISO departs Sasebo for Brunei Bay, Borneo, escorted by DesDiv 30's YUZUKI (F), and UZUKI. JUNYO carries 18-inch shells for super-battleship YAMATO and heavy caliber shells for Kurita's other battleships. Also embarked are "Shinyo" suicide boats for Manila. The other various ships carry naval ammunition, supplies and 800 paratroopers from Major Shirai Tsuneharu’s IJA’s 3rd Raiding Regiment, 2nd Raiding Brigade, bound for Manila. Destroyer AKIKAZE joins the group when west of Okinawa.
1 November 1944:
Arrives at Mako.
2 November 1944:
Departs Mako, still escorted by KISO, UZUKI, YUZUKI and AKIKAZE.
3 November 1944:
160 miles W of Cape Bolinao, Luzon, Philippines. Lt Cdr (later Admiral/CINCPACFLT) Bernard A. Clarey’s (USNA ’34) USS PINTADO (SS-387) at 1645 (H-time) receives an "Ultra" signal from ComSubPac's codebreakers alerting him that a Japanese carrier, "a battleship or cruiser" and three destroyers are heading S through the Formosa Strait. Clarey's wolfpack of PINTADO, JALLAO (SS-368) and ATULE (SS-403) with LtCdr John P. Roach's (USNA ’32) pack of HADDOCK (SS-231), HALIBUT (SS-232) and TUNA (SS-203) form a picket line to intercept the carrier group.
At 2020 (H-time, 2120 JST), Clarey picks up the carrier flanked by two destroyers with another destroyer ahead and a light cruiser astern. Clarey notes the carrier has a small island forward of amidships. He sets up and fires all six of his bow torpedoes at the carrier's port side; but torpedoes are deliberately intercepted at 2250 by LtCdr Yamazaki Nitaro's escorting destroyer AKIKAZE, which breaks up, upends, and sinks in eight minutes with all hands, 205 officers and men. The other ships are not hit and escape to the West.[Note 2]
6 November 1944:
Evening: arrives at Brunei with shells and supplies for Kurita’s fleet.
8 November 1944:
At 0400, departs Brunei towards Pratas Islands (near the Formosa Strait) with 1st Diversion Attack Force consisting of BatDiv 1's YAMATO and NAGATO, BatDiv 3 KONGO and HARUNA, heavy cruisers HAGURO and ASHIGARA, light cruiser YAHAGI and DesDiv 17's HAMAKAZE, URAKAZE, ISOKAZE, and YUKIKAZE; ASHIGARA, delayed by refueling, is detached and returns to Brunei. Subsequently splits off and heads for Manila with the damaged TONE, KISO, YUZUKI, UZUKI, and SHIGURE. The remainder of the task group makes a feint through the Balabac Strait, then returns to Brunei.
9 November 1944:
At 1900, arrives at Manila. Unloads troops and supplies.
11 November 1944:
At 1100, departs Manila for Kure, with the damaged TONE in company; both ships are escorted by DesRon 2’s SHIGURE, DesDiv 30’s YUZUKI and UZUKI. KISO remains behind.
13 November 1944:
Attacked south of Mako at 0640 (I-time/JST) by LtCdr (later Rear Admiral-Ret) Joseph B. Icenhower’s (USNA ’36) USS JALLAO (SS-368). JALLAO narrowly avoids being rammed by JUNYO when carrier makes a sudden turn and passes within 200 yards. Icenhower fires six stern tubes at carrier's starboard at 1,400 yards as shears away, but no damage is sustained. (JUNYO had apparently been sighted and with TONE misidentified on 12 Nov and excitedly reported as battleship YAMATO headed north!) Arrives safely at Mako that afternoon.
14 November 1944:
Departs Mako for Kure.
15 November 1944:
En-route to Kure; at 2249 ( Item/JST -time) detected by Cdr (later Rear Admiral-Ret) Eugene B. Fluckey’s (USNA ’35) USS BARB (SS-220). Fluckey mis-identifies carrier as Shokaku-class, believed to be new carrier KATSURAGI. Fires five bow tubes at target’s starboard side, and claims one hit on stern at 2327, but in fact, no damage is sustained.Assigned this day to Combined Fleet, CarDiv 1 also consisting of light carrier RYUHO.
23 November 1944:
Departs Kure for Sasebo with DesDiv 41’s FUYUZUKI and SUZUTSUKI.
25 November 1944:
Departs Sasebo for Manila via Mako on a transport mission, still escorted by FUYUZUKI and SUZUTSUKI.
27 November 1944:
Arrives at Mako.
30 November 1944:
At 0725 (H-time, 0825 JST), sighted by LtCdr Frank E. Haylor’s (USNA ’36) USS HAKE (SS-256) outside Manila Bay, but the submarine is too far away to intercept. At 1520, arrives at Manila.
1 December 1944:
At 0500, departs Manila for Mako with DesDiv 41’s FUYUZUKI and SUZUTSUKI and MAKI.
3 December 1944:
At 1145, JUNYO, Desdiv 41 and MAKI arrive at Mako.
5 December 1944:
At 1040, joined at Mako by battleship HARUNA, DesDiv 18’s KASUMI and DesDiv 21’s HATSUSHIMO.
6 December 1944:
At 0040, carrying 200 survivors of the super-battleship MUSASHI, departs Mako with HARUNA, escorted by DesDiv 41’s SUZUTSUKI, FUYUTSUKI, and DesDiv 43’s MAKI. (KASUMI and HATSUSHIMO do not continue with them, but at 1000, head back south).
8 - 9 December 1944:
Between midnight and 0330 the task force is attacked by submarine wolf-pack consisting of Cdr (later Captain-Ret) Ralph E. Styles’ (USNA ’33) USS SEA DEVIL (SS-400), Cdr Clyde B. Stevens’ (USNA ’30) PLAICE (SS-390), and Cdr (later Rear Admiral-Ret) Louis D. McGregor’s (USNA ’30) REDFISH (SS-395). Exactly who hit what and when is not entirely clear, but JUNYO receives two torpedo hits, and destroyer MAKI one. One hit the carrier's starboard engine room, while a second torpedo nips the stem, the explosion breaching the bow plates. About 5,000 tons of water enter the carrier, increasing draught to 10 meters and for a time give her a 18 degree list to starboard, while four petty officers and fifteen men are killed. However, the avgas tanks were empty at the time and there is no fire. Fortunately for the carrier the centerline bulkhead dividing the engine rooms holds despite the starboard engine room being filled. By going ahead on the port engine while applying the rudder somewhat to the left, JUNYO manages to make 13 knots and holds a straight course. At half-speed the carrier manages to escape further attack by entering shoal waters where submarines could not follow. Escorting destroyer MAKI intercepts one of the "fish" and has a smashed bow with four sailors killed, but limps to Nagasaki. [Note 3]
10 December 1944:
At 1100, arrives at Sasebo with HARUNA, still listing considerably to starboard. Captain Shibuya moors her without assistance.
18 December 1944:
Enters drydock.
19 December 1944:
Captain Shibuya is relieved; Sasebo Naval Yard takes over.
1 January 1945:
Reassigned to Cardiv 1, 2nd Fleet.
20 January 1945:
Attacked by land-based bombers while in drydock; claims to have shot down one enemy plane.
28 January 1945:
Undocked.
March 1945:
Further repair and upgrades are abandoned due to lack of materials. Though temporary repairs were completed, these did not include the starboard engine room.
1 April 1945:
Moved from Sasebo docks and anchored in nearby Ebisu Wan (Bay).
20 April 1945:
Cardiv 1 is dissolved.
23 April 1945:
Still at Ebisu Wan (Bay), near Sasebo. Camouflaging begins.
24 April 1945:
Classified as ship of 4th Reserve Fleet.
May 1945:
In Ebisu Wan (Bay), Sasebo. Moored with incomplete carriers KASAGI and IBUKI. Crew is under training, and engaged in camouflage and upkeep.
12 May 1945:
Captain Maehara Tomiyoshi (44) is assigned as commanding officer.
1 June 1945:
Relocated again from Sasebo Navy Yard and anchored in Ebisu Wan (Bay) nearby. Heavy camouflaging continues. Also anchored there are the incomplete carriers KASAGI and IBUKI.
20 June 1945:
Classified as guard ship.
5 August 1945:
Captain Maehara is ordered to strip carrier of all armament and other equipment for defense use elsewhere.
2 September 1945:
Japan surrenders, and the three carriers at Ebisu Wan (Bay), Sasebo area are turned over to the Allies.
8 October 1945:
Boarded by American Naval Technical officers. After inspecting the ship, they declare that repairs to restore the vessel to service even temporarily for repatriation duty would be a waste of resources. Delegated for scrapping.
30 November 1945:
Removed from Navy List.
1 June 1946:
Dismantling begins at Sasebo, completed by 1 August 1947.

Note 1: Recently, there has been some question whether some of the carriers, JUNYO included, received the rocket mount upgrade before the Battle of Marianas. The main clue seems to hinge on what changes prompted the inclination testing on 3 May, 1944, among other hints. However, this remains unresolved at this date and the conventional time of installation has been retained.

Note 2: The Japanese held Lt.Cdr. Yamazaki and his crew’s deed in high regard. The crew of the Junyo erected a monument to pay tribute to Akikaze’s sacrifice in the Kure Naval Cemetery.

Note 3: There is some question about which submarines scored in the 9 December attacks. No less than three U.S. submarines, the USS Sea Devil (SS-400), USS Plaice (SS-390), and USS Redfish (SS-395) attacked the task force. In an attempt to resolve the matter, the patrol reports were examined and compared to IJN records. There is reason to believe the usual credits are in need of adjustment. At the moment, the only attack that can clearly be matched is USS Redfish's final attack with ten torpedoes at extreme range at 0324. Captain Shibuya reported a brace of these passed down both sides of the carrier, but none hit.

Remark:
Though mostly repaired (except for starboard engine) and manned after the torpedo attacks of December 1944, vessel could never be operated due to lack of aircraft and fuel.
Special thanks are due to Gilbert Casse in preparing this TROM, and Bob Hackett, Sander Kingsepp, Bill Somerville and Allyn Nevitt for entries derived from their works.
Thanks go also to John Whitman for info related to ferry/transport missions and to Luke Ruffato of Italy for info related to air operations on Nov ’42.